Crude preparations of herbal cannabis have been used for thousands of years to treat many symptoms, including pain, spasms, and nausea.1 Preparations historically included extracts of roots, leaves, and flowering heads but were not commercially standardized or characterized. Modern pharmacology has identified the principal psychoactive ingredient of cannabis as delta-9-tetrahydrocannabinol; specific cannabinoid receptors have been identified in the central and peripheral nervous system as well as in immune cells, endothelial tissue, and other visceral organs.2 Animal studies have confirmed that many of the effects of cannabis in humanbeings have solid neurophysiologic bases, particularly with respect to pain control.3 The cannabinoid system is, therefore, a major target for drug development.4 [continues 895 words]
In its Marihuana Medical Access Regulations, Health Canada authorizes physicians to prescribe dried cannabis, an unproven and potentially dangerous substance, under the guise of medical treatment. The program is intended to help patients with serious illnesses, such as HIV infection and cancer, but severe arthritis is also listed as an indication. Surveys confirm that chronic pain and arthritis are common reasons for medical cannabis use.1 As analgesics, however, pharmaceutical cannabis products are weaker and less well tolerated than opioids.2 While cannabis users testify to its therapeutic benefits, they also commonly report pleasant psychoactive effects that are easily confused with direct analgesia. [continues 959 words]
